Grinding machine and method of grinding



. June' 12, 1 945.` l I F. J. THELER' Erm. 2,377,982

' f -GRAINDING MACHINE AD METHOD GRINDIIINGy Filed Das. 24," '1942 4.sheets-sheet 1 June l2, A1945. F. J. THELER ETAL GRINDING MACHINE ANDMETHOD oF-GRINDING Filed Dec. 24. i942 #sheets-sheet 2 l s. mmm@ N EWJ.. l T WD L im cab v E. 1 Y B QN u i. h kN Q5 1 n .EM Q N K NNN hv o,Q a

June 12 1945 4 F. J. THELER ETAL 2,377,982

' 'GRlND'ING MACHINE AND METHOD oF GRINDING Filed Dec. 24,` 1942 4sheets-sheet s VJacob Decke @lfb/W1;

INV o `Freoerick 15% er George W zlnns JAN MINN

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Thur S.

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` Patented-.June l2, 1945 UNITED STATES PATENT oFFtcE f GINDING MACHINEAND METHODl F n GBINDING Frederick J. Thiele, George w. mans, and Jacob'l' Decker, Cincinnati, Ohio, assignors to The Cincinnati Milling l acorporation oi.' Ohio Application December 24, 1942, Serial No. 470,314

Q26 claims. (ci. n n) This vinvention relates to grinding machines and amethod oi' grinding. One ofthe objects of this invention is to provide asimple, thoroughly practical and durable grinding machine -foraccurately and economically grinding balls. Another object is to providea construction of the above character which is well adapted to withstandcontinuous hard use and which employs the centerless grinding principle.Another object is; to provide a practical ball grinding attachment whichmay be applied to standard centerless grinding machines. Another objectis to provide an economical and eilicient method of accurately grindingballs in a v centerless grinding machine. Other objects will be in partobvious and in part pointed out hereinvafter.

The invention accordingly consists inthe features of construction,combinations of elements, arrangements of parts, and in the severalsteps `and relation andA order of each of theA same toV one or more ofthe others, all as will be illustratively described herein, andthe scopeof the application of which will be indicated in the following\claims.

In the accompanying drawings in which i's shown one of the variouspossible embodiments of this invention,

Figure 1 is an elevational view of the'machine;

Figure 2 is-a vertical sectional view taken on the line 2-2 'of Figure1, certain parts of the machine being removed `for purposes of clarity;

Figure 3 is an-enlarged view of the left-hand portion of Figure2,'certain of the parts thereof being broken .away for purposes ofclarity;

Figure 4 is a vertical sectional view taken on une' 4,-: of Figure 3;

Figure 5 is a `vertical section taken on the line 5-5 of Figure 3;

I Figure 6 is a vertical section taken on the line Figure 'l Ais ahorizontal section taken on the line 'If-1 of Figure 3 showing the pilotvalve tripping mechanism; Figure 8 is a diagrammaticview of'the hyydraulic control support;

u opposed surfaces of the wheels. Grindingwheel I2 is rotated at 'highspeed in a clockwise direcs Machine Co. Cincinnati, Ohio,

Similar reference characters refer to-similar partslthroughout theseveral views o! the drawings. i v

Referring now to Figure 1,1 the rnachinein-f I cludes a bed Ill having aregulating wheel II and grinding wheel I2 mounted thereon. On theright-hand portion of the machine bed, as viewed in Figure 1, surfaceways I3 (Figure 2) support a carriage Il which is thus movablelongitudinally of the bed; carriage I4 supports the regus lating wheelII and associated mechanism. A

bracket I6 secured to the right-hand portion of f tionI as indicated bythe arrowln Figure i', and

effects a stock removal from the work` in the machine. The regulatingwheel I I, which rotates at a relatively` slow speed in the direction ofthe arrow in Figure l, controls the rate of rotation 'through thegrinding throat formed between the I of the'worlr in the machine. Thus,in operation, the parallel opposed faces of the wheels travel inopposite directions and form a grinding throattherebetweenI in which thework is placed.

Referring now to Figures l, 2, and 3, an attachment, generally indicatedat 2l, is provided for supporting and acting upon the work as it passesregulating and grinding wheels. In generalI this attachment includes aframework supporting a workv rest blade generally indicated at22.(.Figures r2, 4, and 6), aV reciprocating shuttle plate generallyindicated at 23 (Figures 2, 4, and 5) which f to ' and driving mechanismfor the shuttle plate generally indicated at 24. The work is iedv intothe Figure 9 is a vertical sectional view, on an:

enlarged scale, of thatl portion'lof. Figure 2 where workiis ejectediromthe grindingthroat of the machine;A

yFigure "10 is a vertical sectional view taken on the line. III-lu ofFigure 9; and,

lFigure 11 is a vertical sectional view taken on the line`I I-'II ofFigure 3.

moves transversely oi the faces of the wheels.

grinding throat adjacent the left-hand edge` of the grinding wheel, asviewed in-Figure 2, and is moved across plate from left to right,.duringwhich time the work is acted upon by the shuttle plate, 'grindingwheel, and regulating Wheel. all as will be fully describedhereinafter.4

The framework of the attachment includes a the grinding throat by theshuttle' grinding 'and regulating wheels.(Figures 1 and 2) and issecured to slide |4 (Figure 2) by screws 25.

Screws 26 extend through slots in bed plate '25 extending longitudinallyof the machine and thread into carriage |4. Thus, the attachment may beadjusted toward and from the regulating wheel. The vertical supports 21and 28 extend upwardly from and are secured to bed plate 25 adjacent theends thereof and support transverse plate 29 above and parallel to bedplate 25. The rear face of bed plate 25, as viewed in Figures 2 and 4,has a cut-out portion 30 within which work rest blade 22 is positioned.'I'his blade is secured in a vertical position to the bed plate by Y aseries of bolts 3| which extend through vertical slots, such as slot 32(Figures 3 and 4), in the Work restblade, pass through holes in the bedplate of substantially the saine diameter as the shank of the bolts, andthread into nuts 33(Fig ures 2 and 4). 'I'he slots are also ofsubstantially greater width than the diameter of the shank of the bolts3| (Figure 3), thus permitting adjustment of the work rest blade bothvertically and longitudinally with respect to'the bed plate 25.Elevating screws, such as screw34 (Figures 3 and 4), are provided topermit accurate vertical adjustment of the work rest blade tobe made,and longitudinal adjusting screws, such as screw 35 (Figures 3 and 4),are provided for making accurate longitudinal adjustments oi the workrest blade with respect to the bed plate. Longitudinal screw 35 (Figure3) acts against a boss 38 formed on a vertical support 31' secured totherear face of bed plate 25. Thus, the work rest blade is accuratelyadjustable both vertically and longitudinally and, when so adjusted, isclamped in place by boltsl.

.The upper portion 33 of the work rest blade-22 (Figures 4 and 6) istapered to conform to the shape of the grinding wheels, and the upperedge 39 of the blade 22 extends transversely across the faces of thegrinding and regulating wheels (Fig ure 2) parallel to the grindingthroat -formed therebetween. The upper edge 39 (Figures 4 and 6) of thework rest blade is beveled toward the regulating wheel thus insuringrotation of the balls by the regulating wheel. The beveled edge 39 oi'the work rest blade extends a substantial distance to the left of thegrinding and regulating wheels (Figures 2 and 3) which are ofsubstantially the same width.

Shuttle plate 23 is mounted on four rollers 40. 4|, 42, and 43 which arepositioned in the same plane as work rest blade 22 (Figures '4 and 5).As the mounting'of rollers 42 and 43 upon the bed plate is substantialysimilar, detailed description of these rollers will be limited to themounting of roller` 42. As best shown in Figures 3 and 5, a bracket 44is secured by bolts 45 to the rear face of bed plate 25. Bolts 45 extendthrough vertical slots 45 in bracket 44 and thread into bed plate 25.Thus, the position. of bracket 44 with respect to bed plate 25 may beadjusted vertically. A shaft 41 (Figure 5) is mounted in the upper'portion of bracket 44, and roller 42 is As the mounting of rollers 40and 4| (Figure 2) upon vertical supports 21 and 23 is substantiallysimilar, detailed description of the mounting of these rollers lwill belimited to the mounting of roller 40.1 Referring to Figure 3, an arm 4Bis pivotally mounted at 49 on vertical support 21. A'shaft 50 (Figures 3and 5) is mounted in the right-hand end of arm 48, as viewed in Figure3, and is held thereby by a bolt Roller 40 is revolubly mounted on shaft50 above roller 42. A projection 52 (Figure 3) extends outwardly ,fromthe end of arm 48 and is connected by a spring 53 to a bolt 54. Bolt 54extends through and is adjustably connected to a bracket 55 (Figures 3and 5) secured to the rear face of bed plate 25. Spring 53 resilientlyurges arm 43 downwardly and, by adjusting nuts 58, the tension on spring53, and thus the force acting downvwardly upon arm 48, may be increasedor derevolubly mounted upon thisr shaft. Thus, rollers 42 and 43 may beadjusted verticaly with respect to the bedplate (Figure 2) permittingvertical creased.

Referring to Figure 3, an elevating screw 51 threads through a boss 53on vertical support 2l and acts. upon a lug 5l formed on the rear taceoi arm 48. Arm (Figure 2) oi roller 4| is acted upon by an elevatingscrew similar to screw 51, and thus these rollers may be moved upwardlyby their respective elevating screws to permit removal of the shuttleplate. Thus rollers 4U and di are resiliently urged downwardly againstthe upper edges of the shuttle plate and act as effective guides duringmovement of the blade, and the shuttle plate may be conveniently removedfrom the attachment.

As is best shown in Figures 2 and 5, the upper and lower edges 8|, 82,83, and 54 of shuttle plate 23 adjacent the endsthereof are preferablybev-l lbrackets upon which rollers 42 and 43 are mounted and anefficient mounting oi' the shuttleplate is achieved through the actionof the resilient springs urging rollers 40 and 4| downwardly.

As best shown in Figures 2 and 3, the lower edge of the shuttle plate 22has a cut-out portion 65 therein into which the beveled edge 33 o! thework rest blade extends. Referring to Figures 2 and 6, retainer blades33, 51, and 83 are mounted on the lower edge of the cut-out portion ofshuttle plate 23 and are held in position thereon by a clamping plate 42and bolts 1l. 'I'he lower edges of blades 55, 31, and 53 are positionedparallel and in alignment'with the beveled edge 39 of the work restblade. A small wire 1| (Figure 6) is positioned between the upper edgesof the retainer blades and shuttle plateA 23 and may be changed to awire oi' different size for accurately locating the retainer blades'ver' tically with respect to the balls. This permits the blades to beadjusted for balls of ditierent sizes. The retainer blades arepreferably positioned just tar enough above the balls sothat the u lblades do not touch the balls but will prevent them from jumping out of,or piling up in, the grinding throat during operation of the shuttleplate,

'I'he balls 12 are reciprocated in the grinding throat by actuating pins13 (Figure 3) and 14 (Figure 2). Actuating pin 13 is mounted in asupport 15 which is secured to shuttle plate 23 by -screws 19. This pin,which is in alignment with the centers of the balls in the grindingthroat, is threaded through a downwardly projecting portion a of support15, and by turning its head 19, which is positioned in a cut-out'portion 19 of shuttle plate 23, the actuating end 13a of pin 13 may beadjusted with respect to the shuttle plate.

Pin 1I (Figure 2), which extends through a hole 99 in the lower part ofthe right-hand portion of the shuttle plate, threads through an endplate 9|. This pin is also in alignment with the centers of the balls inthe grinding throat, and its position may be adjusted by turning itshead 32. Pins 13 and 1I serve to move the line of balls positioned alongthe edge 39 of the work rest blade to the right and l'eft, as viewed inFigure 2, as shuttle plate 23 reciprocates, all as will be fullydescribed hereinafter.

The portion of the beveled edge 39 of the work rest blade, which extendsto the left of the grinding and regulating wheels as viewed in .Figures2 and 3, is enclosed by a pair of plates 493 and 84 (Figures 2 and 4),secured to the work rest blade 22 by bolts 86 and 81; the plates extendabove the beveled edge `39 of blade 22 (Figure 4) thus to enclose theleft-hand end of the train of balls, as viewed in Figure 2.

As best shown in Figures 2,' 3, and 4, a work. feeding tube 88 extendsupwardly labove the framework of the attachment and is mounted upontransverse plate 29 in any suitable manner. The lower end ofthe tube isaligned with a passageway 89 extending through a block 99. Block 99,which extends downwardly into a cut away portion of shuttle plate 23,ismountedby screws `225 (Figure 4) on a vertical support 31 (Figure 3)connected to bed plate 25.l As is best `shown in Figure 3, bolts 31a and31h secure vertical support 31 to the rear face of bed plate 25 andextend through horizontal slots 299 and 29| in vertical support 31.Thus,the position of vertical support 31 and block 99 may be adjustedlongitudinally with respect to bed plate 25 and shuttle plate 23.

Thelower portion of block 99 has a channel 9| (Figures 3 and 1l) thereinwhich extends lengthwise across the block. This channel is closed to theleft of passageway 89, as viewed in Figure 3, by a block 93 which issecured to block 99by screw 99. The right-hand end of block 93 with theside walls of channel 9| forms -a con- V tinuation of the work feedingpassageway 89 in block 99. A cut-off blade 95 (Figures 3 and l1) isslidably mounted for longitudinal movement with respect to block 99 inthe right-hand section of channel 9|, as viewed in Figure 3. This bladehas a pin `99 (Figures 2 and 3) which extends outwardly through anelongated slot 91 (Figure 2) in the side wall of channel 9|. This pin isconnected to a second pin 93 set in block' 99 by a. spring 99 which actsthrough pin 99 to resiliently urge the cut-ofi blade 95 (Figure 3) tothe left, as viewed in this figure. The cut-off blade 95.is

also provided with a threaded extension |99 thereon upon which a stopmember |9| is mounted for purposes to be disclosed more fullyhereinafter.

Immediately below block 99l a feed plate, generally indicated at |92, ismounted in a eut-oui-l portion of shuttle plate 23, The upper surface ofthisplate retains cut-oft blade 95 within channel 9| (Figures 2 and 3),as viewed in Figure 3, coacts with stop member |9| to situate thecut-o1! blade. As pointed out and its right-hand end |92a,

' The balls accordingly move hereinabove, shuttle plate 23 moves with areciprocatlng action, and when the shuttle plate is positioned at theright-hand end of its stroke, as viewed in Figures 2 and 3, the stringof balls in tube 88 and block 99 rests on the upper flat sur- .face |93of plate |92. To the right o f surface |93 a passageway |94 slantsdownwardly through feed plate |92 and connects with a passageway |95extending through shuttle plate 23 and support 15 (Figures 3 and 11),.

In operation, as shuttle plate 23 moves to the left as viewed in Figure3, movement of feed plate ,|92 permits spring' 99 (Figure 2) tomove thecutoff blade 95 in the same direction. The V-shaped nose |99 oftherblade extends between the two lower balls in'tle string of ballsresting on sur face |93. This separates the lowermost ball from in theshuttle plate. An adjustable stop |91 is provided threading inte theright-hand end scf block 99 which limits the movement of the cutoffblade to the left, as viewedin Figure 3.

When the shuttle plate moves to the right, as viewed in Figure 3, and isapproaching the end. of its stroke in that direction, the end portion|920 of feed plate |92' strikes stop member |9| and thus carries thenose of cut-oil' blade 95 from the path of the balls feeding throughblock 99. downwardly, the lowermost ball'strikingthe at surface |93 offeed plate |92. On the return movement of the shuttle plate, thelowermost ball is again cut off from the stringand fed into the grindingthroat. As is best shown in Figures 2 and 9, the end of actuating pin 14moves a slightly greater distance than thewidth of one ball beyond thebeveled edge 39 of the work rest blade 22 when the shuttle plate 23 isat the end of its stroke to the right, as viewed in Figure 2. The ballwhich moves over the end of edge 39 falls downwardly between plates |98and |99 (Figures 9 and l0) and enters a passageway ||9 (Figure 2) inblock secured to the rear face of bed plate 25. The balls passing fromthe end of passageway ||9 drop into a trough IIZ-by which they leave-themachine. A resilient iinger H3 (Figures 9 and 10) is mounted on boltIII, and its upper end is positioned imrneclial'elt1 above the end ofbeveled edge 39 (Fig-l ure 9) of the work rest blade. This ilngerengages the upper portions of the balls yas they reach the end of thegrinding throat and prevents more than one ball from leaving thegrinding throat each time the shuttle moves to the right. as viewed inFigure 3,-all as will be described hereinafter.

' In operation, each time the shuttle plate moves to the right, asviewed in Figure 2, the balls in the grinding throat are moved byactuating pin 13 against the end of actuating pin 14, and at the end ofthe stroke in this direction, the ball which has been pressed beyondfinger ||3 falls of! the edge of the work rest blade and leaves themachine, nger ||3 holding the remainder of the balls on beveled edge 39.At this time, the end 13a of actuating pin 13 is positioned adjacent theleft edge of passageway |93 as viewed in Figure 3'.

As the plate moves to the left as viewed in F18- ure 3, there is a lostmotion period before the end of actuating pin 1I strikes the ballretained by'nzer m in the grinding throat, and as pin 13 is moving tothe right during this lost motion period, a space is provided at theleft-hand end of the train of balls on the edge o1' the work rest blade.During this same movement a ball is cut ofi' from the string of balls inblock 30 and falls down into passageway |05 into this space. Thus, asthe shuttle plate moves to the right, as viewed in Flgure 2, a ballleaves the grinding throat, and as the'shuttle moves to the left, a ballis added to the right-hand end of the train of balls passingtherethrough. An opening ||8 (Figures 3- and 11) is provided in the rearof passageway |05. 'Ihis opening permits balls to escape from theshuttle plate, should they start to pile up therein due to failure ofthe feeding process.

The hydraulic mechanism 24 (Figure 2) is mounted on the framework of theattachment by supports 22| and 222 which are secured to the bed plateand transverse plate 23, respectively.v Shuttle plate 23 (Figure 3) isdriven by a piston rod |2| which is connected to piston |20 of hydraulicmechanism 24. This rod is connected to the shuttle plate by a swiveljoint |22 and is connected to piston |20 by nut |23. 'I'hereciprocating. movement of piston |20, in its cylinder |24 is controlledby the hydraulic control system diagrammatically shown in Figure 8. Apilot valve, generally indicated at |21, which controls a reversingvalve, generally indicated at |28 (Figure 3), which in turn controlspiston i 20, is mechanically operated by shuttle plate 23.

Referring to Figure 7, a shifter rod |29 extends through a hole invertical support 21. This rod is prevented from rotating within thesupport by a set screw |30( and has adjustable shoulders 3| and 32secured to its opposite ends. It will be noted that the end of set screw|30 engages a slot in shifter rod |29, thus permitting movement of theshifter rod transversely of vertical support 21. Shoulder |3| engages a.slot |33 in the end of the stem |34 of pilot valve |21 and shoulder |32extends forwardly from rod |29 and is positioned in the -path of the endplate |26 of shuttle plate 23. moves to the right, as viewed in Figures3 and 7, end plate |26 strikes shoulder |32 and moves the pilot valvestem |34 'to the right through shifter rod |28 and shoulder 3|, thuschanging the setting of the pilot valve. When the shuttle plate moves inthel opposite direction and approaches the end of its stroke, anadjustable stop |25 on end plate |28 strikes the end of the pilot valvestem, |34 andl moves it to the left to reverse the position of the pilotvalve. Accordingly, movement of the shuttle plate to the left or right,as viewed in Figures 2 and 3, controls the movement of the pilotvalve,and as the shuttle plate approaches the end of its stroke ineither direction, the pilot valve is shifted to reverse the action.

Referring now to Figure l, a casing, generally indicated at |35, isshown which contains a pump, a relief control valve, and a sump. Fromthis casing, pressure and sump conduits |36 and |31, respectively, entera stop control valve |38. A pair of flexible conduits |39 and |40connect stop control valve |38 with hydraulic control mechanism 24.

As best shown in Figure 8, a pump |4| pumps the hydraulic fluid fromsump |42 to stop control valve |38 through conduit |36. In conduit |36between pump 4| and stop control valve |38 a relief valve |43 isprovided to insure a constant pressure. When stop control valve |33 isin its Thus, as the shuttle plate on" position, as indicated by thedotted lines |44, conduit |38 is connected to pressure conduit |39. Thisconduit enters the center portion of both pilot Valve |21 and reversingvalve |28. Sump conduit |31, which connects stop control valve |38 tothe sump, at this time is connected to sump conduit which'in turn isconnected to ports |45 and |46 of pilot valve |21 and ports |41 and |48of reversing valve |28. A pair of conduits |43 and |50 connect reversingvalve |28 to the cylinder within which piston |20 is positioned, and apair of conduits |5| and |52 connect pilot valve |21 to reversing valve|28. In conduits |5| and |52 are check valves |53 and |54 which permitthe hydraulic fluid to flow from the pilot valve |21 to the reversingvalve |28 but prevent flow in the opposite direction. 4These checkvalves are by-passed by choke coils |55 and |56 for purposes to bedisclosed more fully herelnafter.

In operation, when piston |20 has moved shuttle plate 23 to the right,as viewed in Figure 2, its end plate |28 (Figure 7) moves the pilotvalve stem |34 to the right to the position shown in Figure 8. It willbe noted that the pilot valve |21 has an enlarged central spool |51which provides a pressure differential and makes the valve selfactuatingafter the spool passes the center pressure port |58.

After the pilot valve has been moved to the right into the positionshown in Figure 8 by end plate |26 (Figure 7), pressure from conduit |38entering the pilot valve through port |58 leaves this valve throughconduit |5|, passes check.l valve |53, and enters port |10 of thereversing valve. The pressure fluid entering this port moves thereversing valve to the light to the position shown in Figure 8.Hammering of this valve against the end of the cylinder housing isprevented by choke coil |53 which delays the flow of the pressure iluidfrom the opposite end of the cylinder. The fluid leaving' this valvepasses through conduit |52 to pilot valve |21 and thence to the sumpthrough port |46 and sump conduit |40.

When the reversing valve is in the position shown in Figure 8, pressurefluid entering reversing valve |28 through port |60 passes out throughport |13 of the reversing valve into conduit |48. As this conduit entersthe right-hand end of the cylinder enclosing piston |20, piston |20 andshuttle plate 23 move to the left, as viewed in Figure 2.

As the shuttle plate approaches the end of its stroke to the left, asviewed in Figure 2, adjustable stop |25 (Figures 3 and 7) engages theend of pilot valve stem |34. This moves the spool |51 (Figure 8) of thepilot valve to the left of pressure port |58. This places pressure port|58 in communication with conduit |52 which causes the pressure fluid tomove the reversing valve |28 to the left, as viewed in Figure 8; Thisplaces pressure port |60 in communication with conduit |50 which causesthe pressure fluid to enter the right-hand end of piston cylinder |24,thus causing piston |20 to move the shuttle plate to the right, asviewedin Figure 2.

Thus, shuttle plate 23 is moved with a reciprocating action by thehydraulic mechanism generally indicated at 24, and this movement isdlrectly controlled by the shuttle plate through the tripping mechanismshown in Figure 7. The rate of reciprocation of the shuttle plate may becontrolled by regulating the pressure of the fluid in the hydraulicsystem through pressure relief valve I adjusting the position ofshoulders |3| and |32 on shifter rod |29. Preferably the advancingmovement of the balls is equivalent to approxi- 4mately thecircumference of a ball during the movement of the shuttle plate to theright, as viewed in Figure 2.. This gives each ball one completerevolution during the movement of the shuttle plate in this direction.As a ball leaves .the train of balls supported by the work rest blade atthe end of this stroke, and as there is a 'lost Thus, the severalobjects mentioned hereinabove, as well as many others, are successfullyand practically accomplished by the method and apparatus disclosedhereinabove. a

As many possible embodiments may be made ofthe mechanical features ofthe above invention, and as the art herein described might be.

varied in various parts, all without departing from the scope of theinvention, it is to be understood that all matter hereinabove set forth,or y shown inthe accompanying drawings, is tol be interpreted asillustrative and not in a limiting sense.

We claim:

l. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat, work rest meansfor supporting a, train of balls in said grinding throat, and means formoving said balls with a reciprocating movement transverse to the facesmotion period between the time the end of actuating pin 14 engages theball at the right-hand edge of the work rest blade on thev return strokeof theshuttle, the return movement of the balls' is equal toapproximately two-thirds of their circumference, although the strokes ofthe shuttle plate in either direction are equal. vAccordingly, the trainof balls advances approximately the diameter of one ball for eachreciprocation of the shuttle plate. The actual movement of the shuttleplate is preferably slightly greater than the` amounts given hereinabovebecause sufficient lost motion must be introduced to compensate foreccentricities in the balls in the train on the-work rest blade.

In operation, balls are fed into the feeding tube 88 (Figures 2 and 3)andare fed into the train of balls onV the work rest blade one at a timeas described hereinabove. This is controlled by the reciprocation of theshuttle plate. During each.

reciprocation a ball is ejected from the train as described hereinabove.As` the balls pass through v the grinding throat, the regulating wheel(Fig ure l) rotates the balls, and the grinding wheel .removes stockfrom them as irregularities or excess metal of the balls are presented.In'theV removal oi' stock the grinding wheel tends at any i giveninstant to cut along the line of a great circle,

but the simultaneous rotation about another axis continually changes thedirection of the great circle along which the cutting takes place. Thusthe total effect on the balls. as they' are passed through the'throatrotated by the shuttle results in a true sphere whose surface iscompletely defined by the continuous cutting along lines at a constantradius from the center of the sphere. Metal is never removed below theexact diameter of the sphere, for that diameter is determined by l thedistance from the grinding surface to the coacting point 'on theregulating wheel. In llike manner, the metal in no direction and atV 'nopoint exceeds this precise diameter, for such metal is ground away bythe cutting actionv which has been brought to bear upon every point onthe for rotating a train of balls in the grinding throat of said wheelsas said -balls move through said grinding throat.

2. In` apparatus of the nature described, in combination, a grindingwheel, a regulating' wheel formed between the grinding and regulatingWheels in a direction toward the grinding wheel, means for supportingsaid balls in said grinding throat, and reciprocating shuttle means forro- 0 tating said balls in directions transverse to the direction ofrotation of said |wheels as said balls pass through said grindingthroat.

3. In apparatus pcf-the nature described, in combination, a grindingwheel, a regulating wheel 5 for rotating a train of balls in thegrinding throat formed between the grinding and regulating v vlwheels ina direction toward the grinding wheel, means for supporting said ballsin said grinding throat in substantially a straight line withreto spectto each other, means other than said Wheels for causing the rotation ofsaid balls in a direction transverse to the direction of rotation ofsaid wheels vduring the grinding of said lrballs in said grindingthroat, and means toprevent said 5 balls from moving upwardly out ofsaid grinding throat as they move therethrough.

4. In apparatus of the nature described, in combination. a grindingwheel, a regulating wheel for rotating a train of iballs in the grindingthroat 0 formed between the grinding and regulating wheels in adirection toward the grinding wheel, means for supporting said balls insaid grinding throat, reciprocating actuating means for rotating saidballs in directions `transverse to the d irec- -through said grindingthroat, and means to pre-I surface of the sphere during the travel ofthe n balls through the throat of the machine.

It will thus be seen that a thoroughly eflicient and practical methodand apparatus for grinding balls. on a centerless grinding machinehasbeen a disclosed. The apparatus is in the formof an attachment which maybe installed on standard centerless grinding machines having flatwheels. This results .in a material saving of abrasive material, moreefficient operation; and b alls which-are accurately ground. A

vent said balls from moving upwardly out of said grinding throat as theymove therethrough.

-5. Invapparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat therebetween,said grinding and regulating wheels having straight operative faces,Awork rest means having a substantially straight work supporting edge,means for feeding balls onto said work rest means adjacent one edge'ofsaid grinding wheel, means for removing balls from said work rest meansadjacent the other edge of said grinding. wheel, and actuating means for moving said balls through said grinding throat and causing them torotate transversely to the direction of rotation imparted to said ballsby said regulating wheel during ythe actual grinding of said ballsinsaid throat.

6. In apparatus` of the nature described, in

tion of rotation of said wheels as said balls pass combination, agrinding wheel and a regulating wheel forming a grinding throattherebetween, work rest means, means for feeding balls onto said workrest means adjacent one edge of said grinding wheel, means for removingballs from said work rest means adjacent the other edge of said grindingwheel, actuating means for moving said balls through said grindingthroat and f or causing them to rotate transversely to the direction ofrotation of said wheels, and retainer means positioned above said workrest means for preventing the balls from moving upwardly out 01' 'thegrinding throat.

7. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat therebetween,work rest means, means for feeding balls onto said work rest meansadjacent one edge of said grinding wheel, means for removing balls fromsaid work rest means adjacent the other edge of said grinding wheel,actuating means .for moving said balls through said ygrinding throat andfor causing them to rotate transversely to the direction of rotation or"said wheels, and retainer means positioned above said work rest meam forpreventing the ballsfrom moving upwardly out of the grinding throat,said retainer means and said work rest means being adjustable toward andfrom each other.

8. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat therebetween,work rest means, means :for feeding balls onto said work rest meansadjacent one edge of said grinding wheel, means for removing balls fromsaid work rest means adjacent the other edge of said grinding wheel,reciprocating actuating means for causing said balls to rotate indirections to the right and left of the direction of rotation impartedto said balls by said regulating wheel, and means for causing themovement of said balls through said grinding throat.

9. In apparatus of the nature described, in

means transverse to the direction of rotation of said wheels, andretaining means positioned above said train of balls to prevent movementof said balls upwardly out of the grinding throat.

12. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel having a grinding throat formedtherebetween, means for supporting a train of balls in said grindingthroat, `a shuttle plate, means for moving said shuttle plate with areciprocating action, means on said shuttle plate for acting against theends of the train' of balls positioned in said grinding throat, wherebysaid balls are rotated in both directions by said actuating meanstransverse to the direction of rotation of said wheels, and retainingmeans positioned above said train of balls to prevent movement of saidballs upwardly out of the grinding throat, said work supporting meansand said retaining means being adjustable toward and from each other.whereby the position of said balls in said grinding throat may be variedto accommodate balls of dii-ferent sizes.

13. In apparatus of the nature described, in combination, a grindingwheel, a regulating wheel for rotating a ball positioned in the grindingthroat formed between the grinding and regulating wheels, said ballbeing rotated by said regulating wheel in a direction toward saidgrinding wheel, and reciprocating shuttle means acting upon said ball torotate said ball in directions transverse to the direction of rotationof said y wheels.

combination, a grinding wheel and a regulating wheel forming a grindingthroat therebetween,

a, work rest blade positioned .transversely of the face of said grindingwheel and adapted to support a train of balls in said grinding throat, areciprocating shuttle adapted to move transversely of the face of saidgrinding and regulating wheels, yand means on said shuttle for cans--.ing said balls to rotate in directions transverse tothe direction ofrotation of said wheels.

10. In apparatus'of the nature described, in combination,a'grindingwheelrfand a regulating wheel having a grinding throat formedtherebetween, means for supporting a trainof balls in said grindingthroat, a shuttle plate, means for moving said shuttle plate with areciprocating action; and means on said shuttle plate for acting againstthe ends of the train of balls positioned in said grinding throat,whereby said balls are rotated in both directions by said actuatingmeans transverseto the direction of rotation of said wheels.`

11. In apparatus of the nature described.`in-

combination, a grinding wheel and a regulating wheel having'a grindingthroat formed therebetween, means forqsupporting a train of balls in said grinding throat, a shuttle plate, means for .moving -said shuttleplate with a lreciprocating action,`means on said shuttle'plate rforacting.

against A,the ends of the train of balls positioned Ain saidgrindingthroat,'-'whereby said balls are rotated in both directions by saidactuating als 14. In apparatus of the nature described, in combination,a grinding wheel and a regulating wheel forming a grinding throattherebetween, work rest means for supporting balls in said grindingthroat, means for feeding said balls into said grinding throat, means topermit removal of said balls from said grinding throat, andreciprocating means acting upon said balls in said grinding throat tomove said balls in directions transverse to the faces of said wheels.

15. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat therebetween,work rest means for supporting a train of balls in said grinding throat,means-for feeding said balls into said grinding throat, means to permitremoval of said balls from said grinding throat, and oscillating meansacting upon the ends of said train of balls in said grinding throat tomove said train of balls with a reciprocating movement transverse to thefaces of said-wheels.

16. In apparatus of the nature described, in`

in said vgrinding throat, reciprocating means, and

means on said reciprocating means acting on the ends of said train ofballs on said work rest means to oscillate said train of ballstransversely with respect to the faces o1' said wheels.

17. In apparatus of the nature described, in combination, a grindingwheel and a regulating wheel forming .a grinding throat therebetween,

' work rest means for supporting a train oi' balls l means to preventsaid balls from moving upwardly in said grinding throat, reciprocatingmeans,

means on said reciprocating means acting on the ends of said train oi"balls on said work rest means `to oscillate-said trainof ballstransversely with respect to the faces of said wheels, and

out of said grinding throat during the oscillation of said train ofballs.

18. In apparatus ofthe nature described, in

combination, a grinding wheel and a regulating wheel forming a 'grindingthroat therebetween, work rest means for supporting a train of balls insaid grinding throat, reciprocating shuttle ,means for moving said trainof balls in directions transverse to the faces of said wheels, hydraulicmeans for driving said shuttle means, and tripping mechanism operated bysaid shuttle means for controlling the direction of movement and lengthof stroke of said hydraulic driving means.

l 19. In apparatus of the nature described, in combination, a grindingwheel and a regulating Vwheel forming a grinding throat therebetween,

work' rest means for supporting a train of balls in ysaid grindingthroat, reciprocating shuttle means for moving said train of balls indirections transverse in the faces of saidwheels, means controlled bymovement of said shuttle means for feeding balls'to said train of balls,and means controlled by said shuttle means for removing balls from saidtrain ci balls.

v20. In apparatus of the nature described, in

combination, a grinding wheel and a regulating wheel forming 'a`grinding throat therebetween,

` fworlr vrest means for supporting a train of balls in said grindingthroat, reciprocating shuttle means for'moving said train of balls indirections transverse to the faces of said wheels,

'means controlled by movement of said shuttle means forfeeding balls tosaid train of balls,

means controlled by said shuttle means for removing balls from saidtrain of balls, and `means on said shuttle means for retaining saidballs in said grinding throat.

21. I'he herein described art which includes the steps of, supporting aplurality of balls, grinding said balls in the general direction of themeans by which saidv balls are supported, applying a rotating force tosaid balls in substantially the opposite direction on sidessubstantially opposite to the sides being ground, and

f moving said balls during said grinding with a reciprocating actiontransverse to the direction 22. In apparatus of the nature described, incombination, a grinding wheel and a regulating wheel having a grindingthroat therebetween,

' said grinding wheel and said regulating wheel 23. In apparatus'of thenature described, in combination. a grinding wheel and a regulatingwheel having a grinding throat therebetween,

said grinding wheel and saidregulating wheel,

having `substantially straight operative faces, means for supporting a,train of balls in said' grinding throat in a substantially straightline as said balls are being ground in said grinding throat.

24. In apparatusof the nature described, in combination, a grindingwheel and a regulating wheel forming a grinding throat, said grindingwheel and regulating wheel being adjustable toward and fromeach other,work rest means for supporting a train of balls in said grinding throat,said work rest means being adjustable upwardly and downwardly in saidgrinding throat, and means for moving said balls with a reciprocatingmovement transverse to the faces of said wheels as said balls passthrough said grinding throat.

25. 'I'he herein described art which vincludes the steps of, supportinga4 train of ballsvin a grinding throat formed between a grinding wheeland a regulating wheel, grindingv said balls in the general direction ofthe means by which said balls are supported, said regulating wheelrotating said balls to move their surfaces adjacent the grinding wheelin substantially the same direc'- tion as .the 'adjacent` surface of thegrinding wheel, and moving said train of balls during grinding' indirections transverse to the direction of rotation of saidwheels with areciprocating action and with an excess of forward move- ,Y

ment to successively move said balls through and out of said grindingthroat.

26. The herein described art which includes thevsteps of, supportingaplurality of balls in a grinding throat formed between a grinding Wheeland a regulating wheel, grinding said balls in.

moving said balls with a reciprocating action transverse to the faces oisaid wheels.

FREDERICK J. THELER. GEORGE W. BINNS. JACOB DECm.

